The present invention relates to an interface for controlling musical instrument synthesizers. In one aspect, the present invention allows musicians familiar with stringed instruments to use their musical skill to control electronic music synthesizers.
According to one aspect of the invention, there is provided a synthesizer controller based on a guitar interface, but the invention is not limited to use with guitars and can be utilized in any other stringed instrument form-factor.
A typical stringed instrument has two means for activating and controlling sounds. The first means controls the loudness or onset of the tone, and the second means controls the pitch of the tone. In a conventional mechanical or electro-mechanical stringed instrument, this is accomplished by strumming, plucking or bowing the strings with one hand to provide the onset and loudness. The fingers of the other hand are used to terminate the string length to define the pitch of the note.
Two types of interfaces for electronic stringed instruments are generally known. The first is based on pitch detection using an electromagnetic, piezo-electric or optical pickup coupled to each string. The pickup converts the string vibrations into an electrical signal and a combination of hardware signal conditioning and software algorithms is then used to convert the electronic signal into information that can be transmitted to a music synthesizer. This may typically be a MIDI (Musical Instrument Digital Interface) device. This method, however, is characterized by a physical delay between the time that the string is plucked and the time that the resulting note is generated. The delay is due to the fact that a significant part of the electrical waveform must be analyzed before a result can be calculated and transmitted. In a normal guitar, the low E string is about 82.4 Hz, so a single cycle of this waveform is 12.1 ms. Typical systems need to acquire more than a single cycle before the pitch can be accurately determined, and this can result in delays that are not pleasing to musicians.
The second method is based on a set of switches in the instrument neck combined with a set of triggers. The switches in the neck are used to define the pitch of the note to be played. The triggers are plucked or strummed and are used to activate the onset of the note. The problem with this type of system is that the switches in the neck are not very guitar-like for musicians familiar with conventional guitars as well as being expensive to implement.